Many attempts have been made over the years to improve the way users interact with computers. In the beginning, cards or tapes with punched holes were used for user input. Punch cards gave way to terminals with alphanumeric keyboards and text displays, which evolved into the modern keyboard, mouse, and graphical-display based graphical user interfaces. Many expect that the use of multi-finger, touch-sensitive user interfaces (“multi-touch interfaces”, such as those described in the references incorporated above, will become widely adopted for interacting with computers and other electronic devices, allowing computer input to become even more straightforward and intuitive.
Users of these multi-touch interfaces may make use of hand and finger gestures to interact with their computers in ways that a conventional mouse and keyboard cannot easily achieve. A multi-touch gesture can be as simple as using one or two fingers to trace out a particular trajectory or pattern, or as intricate as using all the fingers of both hands in a complex sequence of movements reminiscent of American Sign Language. Each motion of hands and fingers, whether complex or not, conveys a specific meaning or action that is acted upon by the computer or electronic device at the behest of the user. The number of multi-touch gestures can be quite large because of the wide range of possible motions by fingers and hands. It is conceivable that an entirely new gesture language might evolve that would allow users to convey complex meaning and commands to computers and electronic devices by moving their hands and fingers in particular patterns.